1. Field of Invention
The present invention relates to a gas generator for a restraining device of a vehicle, such as an airbag apparatus.
2. Description of the Related Art
As a gas generator using a gas generating agent, there is known one in which an igniter is accommodated in a cylinder disposed in a central portion of a housing and the outside of the cylinder is a combustion chamber accommodating a gas generating agent. In such a gas generator, when the igniter is activated, a flame and the like are ejected from a hole formed in the cylinder to the combustion chamber, whereby the gas generating agent is ignited. At this moment, because the hole is formed above the igniter, the gas generating agent on the upper side of the combustion chamber is ignited and burnt by the flame, while the gas generating agent on the lower side is ignited and burnt by combustion of another gas generating agent. Therefore, the ignition property of the gas generating agent on the lower side is degraded.
JP-A No. 2005-53382 discloses a gas generator, wherein an inner cylindrical body 16 is disposed within a housing 3 formed by an initiator shell 1 and a closure shell 2, and a combustion chamber 5 is formed so as to surround the inner cylindrical body 16 and is filled with a gas generating agent 4. The inner cylindrical body 16 is disposed in a central portion of the housing 3, and an enhancer 17 and an igniter 18 are disposed therein.
U.S. Pat. No. 5,458,371 discloses an airbag inflator. A cylindrical member 120 is disposed inside a housing 102 formed by a diffuser cover 104 and base wall 106, the inside of the cylindrical member 120 is an ignition chamber 124, while the outside is a combustion chamber/filter chamber 132. A hole 130 communicating the both chambers with each other is formed with inclination on a circumferential wall surface of the cylindrical member 120. A combustion product generated from the ignition chamber 124 is discharged toward the lower side of the combustion chamber/filter chamber 132 (base wall 106 side).